{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T11:05:19Z","timestamp":1790766319171,"version":"4.1.0"},"reference-count":68,"publisher":"Wiley","issue":"4","license":[{"start":{"date-parts":[[2022,12,9]],"date-time":"2022-12-09T00:00:00Z","timestamp":1670544000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008982","name":"National Science Foundation of Sri Lanka","doi-asserted-by":"publisher","award":["2030859"],"award-info":[{"award-number":["2030859"]}],"id":[{"id":"10.13039\/501100008982","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008982","name":"National Science Foundation of Sri Lanka","doi-asserted-by":"publisher","award":["ECCS\u20102025158"],"award-info":[{"award-number":["ECCS\u20102025158"]}],"id":[{"id":"10.13039\/501100008982","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Journal of Anatomy"],"published-print":{"date-parts":[[2023,4]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Major transformations in the locomotor system of archosaurs (a major clade of reptiles including birds, crocodiles, dinosaurs, and pterosaurs) were accompanied by significant modifications to ankle anatomy. How the evolution of such a complex multi\u2010joint structure is related to shifts in ankle function and locomotor diversity across this clade remains unclear and weakly grounded in extant experimental data. Here, we used X\u2010ray Reconstruction of Moving Morphology to reconstruct skeletal motion and quantify the sources of three\u2010dimensional ankle mobility in the American alligator, a species that retains the ancestral archosaur ankle structure. We then applied the observed relationships between joint excursion and locomotor behaviors to predict ankle function in extinct archosaurs. High\u2010resolution reconstructions of<jats:italic>Alligator<\/jats:italic>skeletal movement revealed previously unseen regionalized coordination among joints responsible for overall ankle rotation. Differences in joint contributions between maneuvers and steady walking parallel transitions in mobility inferred from the ankle structure of fossil taxa in lineages with more erect hind limb postures. Key ankle structures related to ankle mobility were identified in the alligator, which permitted the characterization of ancestral archosaur ankle function. Modifications of these structures provide morphological evidence for functional convergence among sublineages of bird\u2010line and crocodylian\u2010line archosaurs. Using the dynamic insight into the internal sources of<jats:italic>Alligator<\/jats:italic>ankle mobility and trends among locomotor modes, we trace anatomical shifts and propose a mechanistic hypothesis for the evolution of ankle structure and function across Archosauria.<\/jats:p>","DOI":"10.1111\/joa.13801","type":"journal-article","created":{"date-parts":[[2022,12,9]],"date-time":"2022-12-09T13:48:45Z","timestamp":1670593725000},"page":"592-606","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Inner workings of the alligator ankle reveal the mechanistic origins of archosaur locomotor diversity"],"prefix":"10.1111","volume":"242","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1512-9742","authenticated-orcid":false,"given":"Morgan L.","family":"Turner","sequence":"first","affiliation":[{"name":"Department of Ecology, Evolution, and Organismal Biology Brown University Providence Rhode Island USA"},{"name":"Department of Computer Science and Engineering University of Minnesota Minneapolis Minnesota USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1701-0320","authenticated-orcid":false,"given":"Stephen M.","family":"Gatesy","sequence":"additional","affiliation":[{"name":"Department of Ecology, Evolution, and Organismal Biology Brown University Providence Rhode Island USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2022,12,9]]},"reference":[{"key":"e_1_2_9_2_1","doi-asserted-by":"publisher","DOI":"10.1038\/nature12059"},{"key":"e_1_2_9_3_1","doi-asserted-by":"publisher","DOI":"10.1007\/s41513-017-0036-0"},{"key":"e_1_2_9_4_1","doi-asserted-by":"publisher","DOI":"10.1098\/rsif.2011.0687"},{"key":"e_1_2_9_5_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.gr.2020.08.003"},{"key":"e_1_2_9_6_1","doi-asserted-by":"publisher","DOI":"10.1098\/rspb.2008.0110"},{"key":"e_1_2_9_7_1","doi-asserted-by":"publisher","DOI":"10.1080\/03115518.2019.1594380"},{"key":"e_1_2_9_8_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-020-62033-8"},{"key":"e_1_2_9_9_1","doi-asserted-by":"publisher","DOI":"10.1111\/evo.12882"},{"key":"e_1_2_9_10_1","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1002\/jez.589","article-title":"X\u2010ray reconstruction of moving morphology (XROMM): precision, accuracy and applications in comparative biomechanics research","volume":"313","author":"Brainerd E.L.","year":"2010","journal-title":"Journal of Experimental Zoology Part A: Ecological Genetics and Physiology"},{"key":"e_1_2_9_11_1","doi-asserted-by":"publisher","DOI":"10.1139\/z80-301"},{"key":"e_1_2_9_12_1","doi-asserted-by":"publisher","DOI":"10.1525\/california\/9780520246232.003.0009"},{"key":"e_1_2_9_13_1","first-page":"121","volume-title":"Studies in vertebrate evolution","author":"Charig A.J.","year":"1972"},{"key":"e_1_2_9_14_1","doi-asserted-by":"publisher","DOI":"10.1038\/295317a0"},{"key":"e_1_2_9_15_1","doi-asserted-by":"publisher","DOI":"10.1671\/0272-4634(2000)020[0683:ANSOHA]2.0.CO;2"},{"key":"e_1_2_9_16_1","first-page":"168\u2013178","article-title":"The ankle joint in some early archosaurs","volume":"75","author":"Cruickshank A.R.I.","year":"1979","journal-title":"South African Journal of Science"},{"key":"e_1_2_9_17_1","doi-asserted-by":"publisher","DOI":"10.1038\/317715a0"},{"key":"e_1_2_9_18_1","first-page":"131","article-title":"A late Upper Triassic sphenosuchid crocodilian from Wales","volume":"27","author":"Crush P.J.","year":"1984","journal-title":"Palaeontology"},{"key":"e_1_2_9_19_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-020-70175-y"},{"key":"e_1_2_9_20_1","doi-asserted-by":"publisher","DOI":"10.1098\/rstb.1965.0003"},{"key":"e_1_2_9_21_1","doi-asserted-by":"publisher","DOI":"10.1002\/ar.22863"},{"key":"e_1_2_9_22_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41586-022-05284-x"},{"key":"e_1_2_9_23_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1469-7998.1991.tb03786.x"},{"key":"e_1_2_9_24_1","first-page":"432","volume-title":"Mesozoic birds: above the heads of dinosaurs","author":"Gatesy S.M.","year":"2002"},{"key":"e_1_2_9_25_1","doi-asserted-by":"crossref","first-page":"244","DOI":"10.1002\/jez.588","article-title":"Scientific rotoscoping: a morphology\u2010based method of 3\u2010D motion analysis and visualization","volume":"313","author":"Gatesy S.M.","year":"2010","journal-title":"Journal of Experimental Zoology Part A: Ecological Genetics and Physiology."},{"key":"e_1_2_9_26_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1558-5646.1996.tb04496.x"},{"key":"e_1_2_9_27_1","doi-asserted-by":"publisher","DOI":"10.1111\/joa.13635"},{"key":"e_1_2_9_28_1","doi-asserted-by":"publisher","DOI":"10.3374\/014.052.0102"},{"key":"e_1_2_9_29_1","doi-asserted-by":"publisher","DOI":"10.1115\/1.3138397"},{"key":"e_1_2_9_30_1","doi-asserted-by":"publisher","DOI":"10.1080\/02724634.1995.10011574"},{"key":"e_1_2_9_31_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.crpv.2005.09.002"},{"key":"e_1_2_9_32_1","doi-asserted-by":"publisher","DOI":"10.1242\/jeb.101428"},{"key":"e_1_2_9_33_1","doi-asserted-by":"publisher","DOI":"10.1242\/jeb.145383"},{"key":"e_1_2_9_34_1","first-page":"1","article-title":"Allosaurus fragilis: a revised osteology","volume":"109","author":"Madsen J.H.","year":"1976","journal-title":"Utah Geological and Mining Survey Bulletin"},{"key":"e_1_2_9_35_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.2023513118"},{"key":"e_1_2_9_36_1","doi-asserted-by":"publisher","DOI":"10.1206\/0003-0090(2007)302[1:TAOEOA]2.0.CO;2"},{"key":"e_1_2_9_37_1","doi-asserted-by":"publisher","DOI":"10.1038\/nature22037"},{"key":"e_1_2_9_38_1","doi-asserted-by":"publisher","DOI":"10.1080\/02724634.2017.1396539"},{"key":"e_1_2_9_39_1","doi-asserted-by":"publisher","DOI":"10.1002\/ar.24287"},{"key":"e_1_2_9_40_1","doi-asserted-by":"publisher","DOI":"10.1098\/rspb.2005.3426"},{"key":"e_1_2_9_41_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.1180350"},{"key":"e_1_2_9_42_1","doi-asserted-by":"publisher","DOI":"10.1017\/S0022336000041317"},{"key":"e_1_2_9_43_1","first-page":"79","article-title":"Coossified tarsometatarsi in theropod dinosaurs and their bearing on the problem of bird origins","volume":"42","author":"Osm\u00f3lska H.","year":"1981","journal-title":"Palaeontologia Polonica"},{"key":"e_1_2_9_44_1","doi-asserted-by":"publisher","DOI":"10.1525\/california\/9780520242098.003.0010"},{"key":"e_1_2_9_45_1","doi-asserted-by":"publisher","DOI":"10.1002\/jez.b.23022"},{"key":"e_1_2_9_46_1","first-page":"21","article-title":"Were pterosaur ancestors bipedal or quadrupedal? Morphometric, functional, and phylogenetic considerations","volume":"28","author":"Padian K.","year":"2008","journal-title":"Zitteliana"},{"key":"e_1_2_9_47_1","doi-asserted-by":"publisher","DOI":"10.1080\/02724634.2017.1364651"},{"key":"e_1_2_9_48_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1475-4983.2009.00924.x"},{"key":"e_1_2_9_49_1","doi-asserted-by":"publisher","DOI":"10.1017\/S0094837300009003"},{"key":"e_1_2_9_50_1","doi-asserted-by":"publisher","DOI":"10.1080\/02724634.1993.10011511"},{"key":"e_1_2_9_51_1","doi-asserted-by":"publisher","DOI":"10.1671\/0272-4634(2008)28[363:ANSAFT]2.0.CO;2"},{"key":"e_1_2_9_52_1","volume-title":"R: a language and environment for statistical computing","author":"R Core Team","year":"2020"},{"key":"e_1_2_9_53_1","doi-asserted-by":"publisher","DOI":"10.1242\/jeb.201.18.2559"},{"key":"e_1_2_9_54_1","volume-title":"Osteology of the reptiles","author":"Romer A.S.","year":"1956"},{"key":"e_1_2_9_55_1","doi-asserted-by":"publisher","DOI":"10.1002\/ar.24298"},{"key":"e_1_2_9_56_1","first-page":"395","article-title":"The morphological and functional evolution of the tarsus in amphibians and reptiles","volume":"78","author":"Schaeffer B.","year":"1941","journal-title":"Bulletin of the American Museum of Natural History"},{"key":"e_1_2_9_57_1","doi-asserted-by":"publisher","DOI":"10.1080\/02724634.1991.10011426"},{"key":"e_1_2_9_58_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.284.5423.2137"},{"key":"e_1_2_9_59_1","doi-asserted-by":"publisher","DOI":"10.1127\/njgpa\/180\/1990\/21"},{"key":"e_1_2_9_60_1","doi-asserted-by":"publisher","DOI":"10.1080\/02724634.1994.10011538"},{"key":"e_1_2_9_61_1","doi-asserted-by":"publisher","DOI":"10.1080\/02724634.2010.501450"},{"key":"e_1_2_9_62_1","volume-title":"Function and evolution of the hind limb in Triassic archosaurian reptiles","author":"Sullivan C.S.","year":"2007"},{"key":"e_1_2_9_63_1","doi-asserted-by":"publisher","DOI":"10.1080\/03115518008558970"},{"key":"e_1_2_9_64_1","doi-asserted-by":"publisher","DOI":"10.1144\/SP379.15"},{"key":"e_1_2_9_65_1","doi-asserted-by":"publisher","DOI":"10.1098\/rsbl.2020.0309"},{"key":"e_1_2_9_66_1","doi-asserted-by":"publisher","DOI":"10.1242\/jeb.242240"},{"key":"e_1_2_9_67_1","doi-asserted-by":"publisher","DOI":"10.1098\/rstb.1970.0028"},{"key":"e_1_2_9_68_1","doi-asserted-by":"publisher","DOI":"10.1144\/SP379.7"},{"key":"e_1_2_9_69_1","doi-asserted-by":"publisher","DOI":"10.2307\/1442557"}],"container-title":["Journal of Anatomy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/joa.13801","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1111\/joa.13801","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/joa.13801","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,12,2]],"date-time":"2023-12-02T19:07:38Z","timestamp":1701544058000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/joa.13801"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,12,9]]},"references-count":68,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2023,4]]}},"alternative-id":["10.1111\/joa.13801"],"URL":"https:\/\/doi.org\/10.1111\/joa.13801","archive":["Portico"],"relation":{},"ISSN":["0021-8782","1469-7580"],"issn-type":[{"value":"0021-8782","type":"print"},{"value":"1469-7580","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,12,9]]},"assertion":[{"value":"2022-07-12","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-11-20","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-12-09","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}